from binascii import a2b_hex


class Dog:
    '''一次模拟小狗的简单尝试'''

    def __init__(self,name,age):
        '''初始化属性name和age'''
        self.name=name
        self.age=age

    def sit(self):
        '''模拟小狗收到命令时蹲下'''
        print(f"{self.name} is now sitting")

    def roll_over(self):
        '''模拟小狗收到命令时打滚'''
        print(f"{self.name} rolled over !")